I did add a new user and populated the email address and O365 did create the user. However, I dont see it on my 2016 server like i do for the users I migrated and I cant add any additonal smtp addresses to it since it says im using dirsync (AD connect). which i why i am keeping a 2016 server on prem.
Regarding the Hybrid config wizard, you can run it on Exchange 2016 to create the send and receive connectors if you wish, but it isn't strictly necessary to do that. Move of the Hybrid settings are organizational and should move forward to Exchange 2016 without many issues, so you can feasibly add Exchange 2016 and decommission 2010.
As an aside, Office 365 has it's own spam/virus filter on mailflow, so it isn't necessary to have an additional solution for that purpose. If you like the features of your spam/virus filter service, you can certainly keep it, but do realize that it's redundant and that you'll end up having to look through two separate Spam filtering systems if things break, so it can cause delays in support down the line.